Facial Nerve Palsy: Bell’s vs Ramsay Hunt

TL;DR

ENT: Facial Nerve Palsy: Bell’s vs Ramsay Hunt is a frequently examined topic in MRCP Part 1 because candidates must distinguish an idiopathic facial nerve palsy from herpes zoster oticus. Bell's palsy typically presents with isolated lower motor neurone facial weakness and has an excellent prognosis with early corticosteroids, whereas Ramsay Hunt syndrome is characterised by facial palsy with severe ear pain and vesicular eruptions due to varicella-zoster virus reactivation. Knowing the distinguishing features, investigations, treatment and prognostic differences can secure valuable marks in the examination.

Why this matters

Facial nerve palsy is a classic neurological and ENT presentation tested in MRCP Part 1. Examination questions commonly assess whether candidates can distinguish Bell's palsy, the commonest cause of acute unilateral lower motor neurone facial weakness, from Ramsay Hunt syndrome, which results from reactivation of varicella-zoster virus within the geniculate ganglion.

The diagnosis determines management, prognosis and the likelihood of complete recovery. Examiners frequently include subtle clues such as ear pain, vesicles or hearing loss rather than directly naming the condition.

For a complete revision programme, see the MRCP Part 1 overview:https://www.crackmedicine.co.uk/mrcp-part-1/

Scope of the topic

Candidates should be able to:

• Recognise lower motor neurone facial weakness

• Differentiate Bell's palsy from Ramsay Hunt syndrome

• Understand facial nerve anatomy relevant to clinical findings

• Identify associated neurological and ENT symptoms

• Know first-line management and prognosis

The five most tested subtopics

1. Bell's palsy

Bell's palsy is an acute idiopathic lower motor neurone facial nerve palsy, probably related to HSV-1 reactivation causing inflammation and oedema within the facial canal.

Typical features include:

• Sudden onset over 24–72 hours

• Entire ipsilateral face affected

• Forehead cannot wrinkle

• Eye closure impaired

• Drooping mouth

• Altered taste on anterior two-thirds of tongue

• Hyperacusis in some patients

• Reduced lacrimation

There are no vesicles, significant ear pain or hearing loss.

Early corticosteroids within 72 hours significantly improve recovery.

2. Ramsay Hunt syndrome

Ramsay Hunt syndrome results from reactivation of varicella-zoster virus in the geniculate ganglion.

Key features include:

• Severe ear pain preceding weakness

• Vesicular rash involving:

  • External auditory canal

  • Pinna

  • Tympanic membrane

  • Occasionally palate

• Lower motor neurone facial palsy

• Hearing loss

• Vertigo

• Tinnitus

• More severe nerve damage than Bell's palsy

Treatment requires:

• Oral corticosteroids

• Antiviral therapy (usually aciclovir or valaciclovir)

• Eye protection

• Adequate analgesia

Recovery is generally poorer than Bell's palsy.

3. Bell's palsy vs Ramsay Hunt: High-yield comparison

Feature	Bell's palsy	Ramsay Hunt syndrome
Cause	Idiopathic (likely HSV-1)	Varicella-zoster virus
Ear pain	Mild or absent	Severe
Vesicular rash	No	Present
Hearing loss	Rare	Common
Vertigo	Rare	Common
Prognosis	Excellent	Worse
Steroids	Yes	Yes
Antivirals	Usually not required routinely	Recommended

This comparison table is among the highest-yield facts for MRCP Part 1.

4. Examination findings

Remember that both conditions produce a lower motor neurone facial palsy, meaning:

• Loss of forehead wrinkling

• Inability to close the eye

• Flattened nasolabial fold

• Mouth deviation to opposite side

• Reduced blinking

• Bell's phenomenon may be visible

Do not confuse these findings with an upper motor neurone lesion such as stroke, where forehead movement is preserved.

5. Management principles

For Bell's palsy:

• Oral prednisolone within 72 hours

• Lubricating eye drops

• Eye ointment overnight

• Eye patch if needed

• Ophthalmology referral if corneal exposure develops

For Ramsay Hunt syndrome:

• Corticosteroids

• Aciclovir or valaciclovir

• Pain control

• Eye protection

• ENT follow-up if hearing or vestibular symptoms are significant

10 High-yield examination points

1. Bell's palsy is the commonest cause of acute unilateral LMN facial palsy.

2. Ramsay Hunt is caused by varicella-zoster virus.

3. Severe otalgia strongly suggests Ramsay Hunt.

4. Vesicles around the ear are a diagnostic clue.

5. Hearing loss favours Ramsay Hunt.

6. Vertigo is uncommon in Bell's palsy.

7. Steroids are indicated early in both conditions.

8. Antivirals are routinely recommended for Ramsay Hunt.

9. Eye protection prevents corneal ulceration.

10. Ramsay Hunt has a poorer prognosis than Bell's palsy.

Practical examples / mini-cases

Mini-case

A 58-year-old man develops severe left ear pain for two days followed by inability to close his left eye. Examination demonstrates vesicles within the external auditory canal together with complete ipsilateral facial weakness. He also complains of tinnitus.

Question

Which diagnosis is most likely?

A. Bell's palsy

B. Acoustic neuroma

C. Ramsay Hunt syndrome

D. Stroke

E. Otitis externa

Answer: C. Ramsay Hunt syndrome

Explanation

The combination of severe otalgia, vesicular lesions, tinnitus and lower motor neurone facial weakness is highly characteristic of Ramsay Hunt syndrome due to varicella-zoster virus reactivation. Early corticosteroids plus antiviral therapy provide the best chance of neurological recovery.

Practical study-tip checklist

Before your examination, ensure you can confidently answer:

• □ Can I distinguish UMN from LMN facial weakness?

• □ Do I recognise vesicular lesions around the ear?

• □ Do I associate severe ear pain with Ramsay Hunt?

• □ Do I know when antivirals are indicated?

• □ Can I compare prognosis between the two conditions?

• □ Can I identify complications requiring eye protection?

• □ Can I recognise associated vestibular symptoms?

• □ Can I answer image-based questions showing ear vesicles?

Practice similar questions in the Free MRCP MCQs:https://www.crackmedicine.co.uk/qbank/

You can also reinforce this topic through structured teaching in the Expert MRCP lectures:https://www.crackmedicine.co.uk/lectures/

Common pitfalls (5 bullets)

• Confusing Bell's palsy with an upper motor neurone facial weakness caused by stroke.

• Missing vesicular lesions inside the external auditory canal.

• Forgetting that Ramsay Hunt commonly causes hearing loss and vertigo.

• Delaying corticosteroid treatment beyond the optimal therapeutic window.

• Neglecting eye protection, increasing the risk of exposure keratitis.

FAQs

Is Bell's palsy always caused by herpes simplex virus?

No. Bell's palsy is considered idiopathic, although HSV-1 reactivation is the leading proposed mechanism. The diagnosis remains clinical after excluding alternative causes.

Why does Ramsay Hunt syndrome have a worse prognosis?

Varicella-zoster virus causes more extensive inflammation and neuronal injury than Bell's palsy, resulting in lower rates of complete facial nerve recovery.

Should every patient with Bell's palsy receive antivirals?

Current evidence supports early corticosteroids as the primary treatment. Antivirals may be considered in selected severe cases but are routinely recommended for Ramsay Hunt syndrome.

How can I distinguish Bell's palsy from stroke in MRCP questions?

Stroke usually causes an upper motor neurone facial weakness with preserved forehead movement, whereas Bell's palsy affects both the forehead and lower face.

What is the most important immediate complication to prevent?

Corneal damage due to incomplete eye closure. Eye lubrication and protection should begin immediately regardless of the underlying cause.

Ready to start

Mastering common ENT presentations requires repeated exposure to exam-style questions. Strengthen your revision with the Crack Medicine MRCP Part 1 overview, practise hundreds of clinically relevant questions in the QBank, and consolidate your knowledge using comprehensive MRCP lectures designed specifically for physicians preparing for the examination.

Sources

1. MRCP(UK). Examination syllabus. https://www.mrcpuk.org/

2. National Institute for Health and Care Excellence (NICE). Bell's palsy. https://cks.nice.org.uk/

3. National Institute on Deafness and Other Communication Disorders. Facial nerve disorders. https://www.nidcd.nih.gov/

4. Baugh RF et al. Clinical Practice Guideline: Bell's Palsy. Otolaryngology–Head and Neck Surgery.

5. UpToDate. Bell's palsy and Ramsay Hunt syndrome. (Reference for clinician revision.)